Abstract 2682: Efficacy of Combined Use of T-Wave Alternans and Late Potentials in Predicting Lethal Ventricular Tachyarrhythmia Among Patients With Left Ventricular Dysfunction: Insight From the PREVENT-SCD (Prospective Evaluation of Ventricular Tachyarrhythmic Events and Sudden Cardiac Death in Patients With Left Ventricular Dysfunction) Study
Backgrounds. Although T-wave alternans (TWA) and late potential (LP) assessed by signal-averaged electrocardiogram (SAECG) are both reported to have high predictive values for lethal ventricular tachyarrhythmic events (VTEs) in patients (pts) with left ventricular (LV) dysfunction, the efficacy of combined use of TWA and SAECG has not been fully evaluated.
Methods. This study was a multicenter, prospective registry of pts with LV ejection fraction <<26>40%, designed to evaluate the predictive value of TWA and other risk factors for lethal VTE. The primary endpoint (PE) was composite of sudden cardiac death, resuscitated ventricular fibrillation (VF), or appropriate ICD therapy for VF.
Results. Among the 453 pts enrolled, 280 were eligible for the TWA test. The results were negative (TWA−) in 82 (29%), positive or indeterminate (TWA+) in 198 (71%). SAECG as optional test was performed in 240 pts, 94 (39%) of whom had positive LP. Both TWA and LP data were available in 205 pts (TWA−/LP− 41 pts; TWA−/LP+ 16 pts; TWA+/LP− 87 pts; TWA+/LP+ 61 pts). The median of follow-up was 3.0 years. The 3-year event free rate from PE was significantly higher in TWA− pts (97.0%) as compared with both TWA+ pts (89.5%, P=0.037) and those ineligible for the TWA test (84.4%, P=0.003). LP− pts had significantly higher event free rate from PE as compared with LP+ pts (94.4% vs. 80.3%, P=0.0005). Among pts with both TWA and LP data, the 3-year event free rate from PE was 100% in TWA−/LP−, 83.1% in TWA−/LP+, 91.5% in TWA+/LP−, and 83.3% in TWA+/LP+ groups.
Conclusions. Absence of LP enhanced the negative predictive ability of TWA for lethal VTEs. TWA−/LP+ pts had substantial risk for lethal VTEs.